生姜叶片氮含量的高光谱遥感估算模型研究

发布时间：2019-03-31 07:56

【摘要】：作物叶片氮含量的快速估算对于及时了解作物长势、病虫害监测以及产量评估具有重要意义。该文以经济作物生姜为研究对象,获取了2015年4月-9月不同品种、不同生育期和不同氮肥梯度下生姜叶片的高光谱和氮含量数据,对比分析了比值植被指数、归一化植被指数、植被指数组合形式对生姜叶片氮含量的估算效果。在此基础上,基于波段组合算法,筛选出了生姜叶片氮含量的敏感波段,并构建了两个新型光谱指数NDSI_((754,713))和RSI_((754,713))。结果表明,所选择的植被指数中,MCARI(705,750)/OSAVI(705,750)对生姜叶片氮含量估算效果最好,模型精度R~2、RMSE和RE分别为0.73、0.27、11.64%;利用波段组合算法构建的归一化光谱指数NDSI(754,713)对生姜叶片氮含量估算效果要优于MCARI(705,750)/OSAVI(705,750),模型估算精度R~2达0.83,使用的敏感波段713 nm与754 nm均位于植被的"红边"区域。对所建模型进行验证,叶片氮含量的预测值和实测值具有较好的一致性,验证样本R~2为0.78,RMSE为0.20,RE为9.81%。上述分析结果可为农业管理部门及时掌握生姜长势信息、制定施肥策略提供技术支持。
[Abstract]:The rapid estimation of nitrogen content in crop leaves is of great significance for understanding crop growth, pest monitoring and yield assessment in time. In this paper, the hyperspectral and nitrogen content data of ginger leaves of different varieties, different growth stages and different nitrogen fertilizer gradients from April to September 2015 were obtained, and the ratio vegetation index (NDVI) was compared and analyzed. The effect of normalized vegetation index and vegetation index combination on the estimation of nitrogen content in ginger leaves. On this basis, based on the band combination algorithm, the sensitive band of nitrogen content in ginger leaves was screened, and two new spectral indices NDSI_ (754713) and RSI_ (754713).) were constructed. The results showed that, MCARI (705750) / OSAVI (705750) had the best effect on the estimation of nitrogen content in ginger leaves. The model accuracy was 0.73, 0.27 and 11.64%, respectively, and the RMSE and RE were 0.73, 0.27 and 11.64%, respectively. The normalized spectral index NDSI (754713) constructed by band combination algorithm is superior to MCARI (705750) / OSAVI (705750) in estimating nitrogen content in ginger leaves. The sensitive bands 713 nm and 754 nm are located in the "red edge" area of vegetation. The results showed that the predicted and measured values of nitrogen content in leaves were in good agreement with each other. The results showed that the predicted and measured values of nitrogen content in leaves were 0.78, 0.20 and 9.81%, respectively, and that of RMSE and RE were 0.78, 0.20 and 9.81%, respectively. The above analysis results can provide technical support for agricultural management department to grasp the growth information of ginger in time and to formulate fertilization strategy.
【作者单位】：重庆文理学院林学与生命科学学院;重庆文理学院特色植物研究院;
【基金】：国家自然科学基金项目(41401419) 重庆市教委科学技术研究项目(KJ1501123) 重庆文理学院学生科研项目(XSKY2016089)~~
【分类号】：S632.5;S127

【相似文献】